The third Gordon Research Conference (GRC) on Hormone Action in Development and Cancer will be held July 26-31, 2009 at the Holderness School in Plymouth, NH. It was designed to merge three distinct yet overlapping fields of Hormone Action, Development, and Cancer Biology into one ongoing conference that will lead to cross-fertilization of ideas and knowledge on the underlying molecular and cellular mechanisms common to each field. It is notable that this GRC is only conference that fully integrates all three topics, making it unique. The central theme of the 2009 GRC is Hormonal Regulation of Development and Cancer: Common Signaling Pathways. It is based on the growing awareness that common and unique signaling pathways that regulate early life developmental growth and differentiation across organs and phyla are also major participants in the development, growth and progression of cancers leading to the concept of cancer as development gone awry. Within this framework, organ site-specific carcinogenesis as well as certain developmental processes are additionally regulated by common mechanisms of hormone action. This conference will specifically focus on hormone-dependent actions that regulate down-stream signaling pathways involved in development and cancer and highlight the dramatic recent advances that are currently shaping this field of research. The meeting will commence with Keynote addresses that will establish the conference theme followed by eight topic sessions over the following days with presentations by leading scientists highlighting new information on hormone action, hormonal regulation of developmental events in diverse phyla, developmental pathways gone awry in cancer, steroid action in breast and prostate cancer, hormonal carcinogenesis at various sites and through alternate pathways, effects of environmental endocrine disruptors on development and cancer, epigenomic mechanisms in development and cancer under the control of hormones, and novel approaches for translational research. The conference has been organized to integrate these various topics throughout the meeting to permit open and informative discussions, introduce new paradigms and lead the field forward towards novel discoveries. The GRC represents a unique venue for promoting unfettered interchange of scientific ideas through its format of extensive discussion periods at each session, ample free time to encourage informal interactions, and exchanges at poster sessions that will allow attendees to present their latest research findings- all within a college-like atmosphere. There will be multiple opportunities for trainee participation including poster sessions, funding of Trainee Travel Awards and Young Investigator presentations at each morning session. The diverse research topics and translational opportunities represented at the meeting will be of interest not only to the National Cancer Institute (NCI) but also to the National Institute on Diabetes, Digestive and Kidney Disease (NIDDK), the National Institute of Child Health and Human Development (NICHD), the National Institute on Aging (NIA) and the National Institute on Environmental Health Sciences (NIEHS). Public Health Relevance: This meeting will bring together basic and translational scientists and clinicians in the fields of cancer biology, developmental biology and endocrinology in order to foster cross fertilization of ideas and techniques between these scientific communities. This process of communication is essential for the development of new approaches and the identification of translational opportunities for future cancer treatments and chemopreventive strategies. The primary objective of the 2009 GRC on Hormone Action in Development and Cancer is to provide a forum for attendees to learn about the latest advancements, exchange scientific ideas across research field and form new treatment paradigms for application in cancer therapy.